#include <iostream>
#include <cmath>
using namespace std;

int main() {
    int n,x,y;
    int res;
    cin >> n >> x >> y;

    if (y % x == 0)
    {
        res = n - y/x;
    } else {
        res = n - ceil(double(y) / double(x));
    }

    if (res < 0) {
        res = 0;
    }
    cout << res;
    return 0;
}